At first it seemed rendering scripts would be very handy. I have a project and I need to create different variations, each with a different output file and with different tracks enabled or disabled in the timeline. So I set that up and found that it seems to save the entire project along with the script, so that any changes I make to the timeline are ignored -- it just renders the same state of the project as before. What's the point in that? It seems to me the goal of a script would be to tweak various parameters and render the latest version of the project, subject to those parameters.

Now I understand the difficulty -- what parameters do you want to keep the same in each render, and what aspects should be new? It seems that you want to render the current timeline, but certain external factors, such as which tracks are visible/invisible/muted/unmuted should be saved with the script. Also codec and resolution and range of course, but doing just those seems pretty boring. These days many other tools will take a master hi-res and encode it to lower resolutions and lower quality codecs and that's generally good enough for doing that.

Is there a good way to do what I want to do? To be able to specify variants based on which tracks are enabled, and recreate them when needed. Now I have to hand enable/disable all the tracks each time and that's error prone.